Self-locking renewable wing drilling bit



Jan. 29, 1963 E. s. CREEL SELF-LOCKING RENEWABLE wmc DRILLING BIT 2Sheets-Sheet 1.

Filed Dec. 2, 1960 INVENTOR. ERNEST QEE ATTO QMEYS Jan. 29, 1963 E. s.CREEL 3,075,594

SELF-LOCKING RENEWABLE WING DRILLING BIT I Filed D96- 2, 1960 2Sheets-Sheet 2 INVENTOR. j 7 EzuEs'r S-CJZEEL ATTOIZ N EYS Unite Thisinvention relates to drill bits, and more particularly to a drilling bitassembly of the type having detachable blade elements.

A main object of the invention is to provide a novel and improveddrilling bit assembly having detachable blade elements, the assemblybeing relatively simple in construction, being easy to put together andto take apart, and being relatively compact in size.

A further object of the invention is to provide an improved drilling bitassembly which involves relatively inexpensive components, which issturdy in construction, which is easy to dismantle for renewing worncutter wings, and which is provided with ample means for providing aflow of air or water during the drilling operation.

A still further object of the invention is to provide an improveddrilling bit assembly of the type having removabie blade elements, theassembly being self-locking, being of relatively small diameter incomparison with its strength, and being provided with means tofacilitate the escape of water, air and drilling particles during theoperation thereof, whereby to increase the speed of drilling.

Further objects and advantages of the invention will become apparentfrom the following description and claims, and from the accompanyingdrawings, wherein:

FIGURE 1 is a side elevational View, partly in vertical cross section,of an improved drilling bit assembly constructed in accordance with thepresent invention.

FIGURE 2 is an enlarged bottom view of the drilling bit assembly ofFIGURE 1.

FIGURE 3 is an enlarged vertical cross sectional view takensubstantially on the line 3-3 of FIGURE 1.

FIGURE 4 is a horizontal cross sectional view taken on the line 44 ofFIGURE 3.

FIGURE 5 is a perspective view showing the parts of the drilling bitassembly of FIGURES 1, 2 and 3, certain of the parts being shown invertical cross section, and the parts being illustrated in separatedpositions.

FIGURE 6 is an enlarged cross sectional view taken substantially on theline 66 of FIGURE 5.

FIGURE 7 is an enlarged cross sectional view taken substantially on theline 7--7 of FIGURE 5.

FIGURE 8 is an enlarged perspective view of one of the blade elementsemployed in the drilling bit assembly of FIGURES 1, 2 and 3.

Referring to the drawings, 11 generally designates an improved drillingbit assembly constructed in accordance with the present invention. Theassembly 11 comprises a tubular upper supporting member 12 having aninternal ly threaded enlarged top portion 13 adapted to be threadedlyconnected to the bottom end of a drill stem in a conventional manner.The vertical tubular upper supporting member 12 is provided with theannular flange 13 at its lower portion and with the externally threadedbottom end 14 which depends below the annular flange 13, as is clearlyshown in FIGURE 3.

Designated at 15 is a tubular locking member which is rotatably securedin the lower end portion of the upper supporting member 12. Thus, thelocking member 15 is formed with an annular ball race 16 and theexternally threaded bottom end portion 1-4 is recessed at 17 and isformed with a ball race 18 which opposes the ball race 16 of member 15.A ball bearing assembly comprising a plurality of bearing balls 19 aredisposed in the opposing ball races 18 and 16 in the manner illustratedin FIG- 3,075,594 Patented Jan. 29, 1963 URE 3 to provide a rotaryconnection between bottom end portion 14 of the upper supporting member12 and the depending locking member 15.

The bearing balls 19 may be installed by providing a radial access bore20 in the lower end portion of the depending externally threaded member14 through which the bearing balls 1? may be inserted into the spacedefined by the opposing annular races 16 and 18, and after all thebearing balls 19 have been inserted, a suitable steel plug 21 may bewelded in the aperture 20, as shown in FIGURE 3.

The tubular locking member 15 is formed with a plurality of evenlyspaced vertical slots 23 open at their bottom ends and definingrespective spaced locking fingers 24- which are centrally slit at theirlower portions, as shown at 25, the vertical slits 25 extending upwardlyand terminating at a top aperture 26, as shown in FIGURE 3. The verticalslits 25 make the lower end portions of the depending fingers 24relatively resilient, as compared with the top portions of the fingers.

Designated at 27 is a tubular lower supporting member having aninternally threaded upper portion 28 which is threadedly engageable onthe external threads of the member 14 in the manner illustrated inFIGURE 3. As shown in FIGURE 3, the external diameter of the member 27is substantially the same as the flange 13 so that when the internallythreaded portion 28 is fully threaded onto the external threads of themember 14, the external surface of member 27 substantially merges withthe external surface of flange 13 in the manner shown in FIGURES 1 and3. Furthermore, the member 27 is formed with the annular bottom shoulder30 adjacent the lowermost of the internal threads of portion 28 adaptedto provide a bearing surface for the bottom rim of the member 14 whenthe portion 28 is fully threaded onto the externally threaded dependingportion 14 of the upper supporting member 12.

The tubular lower supporting member 27 is formed with a downwardlytapering inner annular wedging surface 32 against which the dependingrelatively resilient lower portions of the fingers 24 are engageable inthe manner illustrated in FIGURE 3. The slits 25 are closed at theirlower end portions by the wedging action when the parts are assembled inthe manner illustrated in FIG- URE 3. The purpose of the slits 25 is tofacilitate the withdrawal of the fingers 24 from the downwardly taperedlower end portion of the internal cavity of member 27 when the assemblyis to be dismantled. Said slits 25 provide enough yieldability toprevent the fingers 24 from sticking in the lower portion of the cavityof member 27 when the assembly is to be dismantled. The yieldability ofthe fingers 24 also facilitates the separation of members 14 and 15 frommember 27 when the upper supporting member 13 is pulled away from thelower supporting member 27.

The lower supporting member 27 is formed with an integral ring portion33 and with vertical slots 34 outwardly adjacent the ring portion 33 andlocated so as to be reg istrable with the vertical slots 23 in thelocking member 15 when the device is in its fully assembled position. Asshown in FIGURE 7, the ring portion 33 spans the vertical slots 34 anddefines flanges or lugs 35 adjacent said vertical slots 34.

Designated at 37 are respective blade members which are formed withnotched portions 38 adapted to interlock with the ring portion 33 at thelugs 35, the blade members 37 being vertically mounted so that theirnotches 38 interengage with the lugs 35 transverse thereto and so thatthe lugs 35 of the ring members 33 are received in the notches 38.Immediately above the notches 38 the blade members 37 are formed withvertical dovetailed locking lugs 39. The vertical surfaces of the slots23 in the lock- 3 ing member 15 are inwardly divergent, as shown in FIG-URE 4, and define dovetail apertures in which the dovetailed lugs 39 arevertically slidable but otherwise lockingly engaged. p I I As shown inFIGURE 3, the bottom ends of the depending lugs 24 are rounded ofi, asshown at 4 0, to facilitate the downward vertical movement of the lugs24 relative to the dovetail vertical lugs 39 when the device is screwedtogether, the lugs 39 being likewise rounded, at their top ends, asshown at 41, to facilitate the interengagement of said lugs 39 betweenthe lugs 24. The resiliency of the lower end portions of lugs 24,provided by the verticalslits 25, further facilitates the lockinginterengagement of the dovetail lugs 39 in the slots 23. The top ends ofthe slots are likewise rounded, as shown at 42, to provide a close fitwith the rounded top end portions 41 of the dovetail lugs 39 It will beseen from FIGURE 8 that the notches 38 define bottom abutment shoulders43 subjacent thereto which serve to transmit downward thrust to theblade members 37 through the ring portion 33, the shoulders 43 thusserving to transmit the downward operating stroke of the drill to theblade members. The blade members are mounted in substantially radialpositions, as shown in FIGURE 2, and are provided with the radi allyextending cutting tip portions 4-4. Each of the blade members isformedwith the spaced reinforcing ribs 45 separated by valleys 46 tofacilitate flow of water, air, and drilling particles past the blademembers so as to facilitate the escape of this material during thedrilling operation. As shown in FIGURE 3, the blade members 37 areformed with the inwardly extending cutting tip portions 44 which extendinwardly to a point substantially adjacent to the vertical center lineof the drilling bit assembly but which are spaced so as to define ampleclearance for water, air, or other drilling fluid to pass downwardlythrough the inside bore 50 of the member 27 and around the externalparts of the blades.

The lower supporting member 27 is formed with suitable brace shoulders51 disposed on opposite sides of the vertical slots 34, serving tostrengthen the lower end of the lower supporting member 27. Theseshoulders 51 also serve to reinforce the portions of member 27 adjacentthe vertical blade members 37 so as to efiectively prevent the cutterblades from bending or twisting out of the member 27 while said memberis being rotated during the drilling operation.

As will be readily apparent, whenever it is necessary to replace a bladeor a number of blades, the device can be dismantled by unscrewing member27 from the externally threaded depending portion 14 of the uppersupporting member 12, the locking member 15 being freely rotatablerelative to member 12 to allow the blade members to be lowered relativeto the vertical slots 23. With member 27 detached from member 14, theblade members may be extracted and new blade members inserted, afterwhich the device may be reassembled by following a procedure reverse tothat above described.

A drilling bit such as above described may be used for various drillingoperations, for example, in sinking holes in the earth for dischargingexplosives in seismograph exploration in locating oil and mineraldeposits. It is also useful in sinking holes for explosives in gravelpits and the like, and it is useful in drilling water wells. Obviously,it may be made in various sizes and may be used in connection with anytype of rotary drilling rig.

While a specific embodiment of an improved drilling bit assembly hasbeen disclosed in the foregoing description, it will be understood thatvarious modifications within the spirit of the invention may occur tothose skilled in the art. Therefore, it is intended that no limitationsbe placed on the invention except as defined by the scope of theappended claims.

What is claimed is:

1. A drilling bit assembly comprising a tubular externally threadedupper supporting member adapted to be connected to a drill stem, atubular locking member rotatably secured in the lower end portion ofsaid supporting member and depending therefrom, the lower end of saidlocking member being formed with a plurality of inwardly divergentvertical slots open at their bottom ends, a tubular lower supportingmember having an internally threaded upper portion threadedly engageableon the external threads of the upper supporting member and formed withan integral ring portion and with vertical slots outwardly adjacent saidring portion and extending above and below same and being registrablewith said first-named vertical slots, and a plurality of blade mem bersformed with notches shaped to receive said ring portion and formed withinwardly flaring locking lugs engageable through said last-namedvertical slots above the ring portion and vertically slidable in andbeing of sufiicient width to be lockingly engageable in the first-namedvertical slots to fasten the blade members to said lower supportingmember when the upper supporting member is threadedly engaged in theupper portion of the lower supporting member.

2. A drilling bit assembly comprising a tubular externally threadedupper supporting member adapted to be connected to a drill stem, atubular locking member rotatably secured in the lower end portion ofsaid supporting member and depending therefrom, the lower end of saidlocking member being formed with a plurality of inwardly divergentvertical slots open at their bottom ends and defining depending lockingfingers therebetween, a tubular lower supporting member having aninternally threaded upper portion threadedly engageable on the externalthreads of the upper supporting member and formed with an integral ringportion and with vertical slots outwardly adjacent said ring portion andextending above and below same and being registrable with saidfirst-named vertical slots, the lower end of said locking member havingan outside diameter sufiiciently large so that said locking fingers arewedgingly engageable in said lower supporting member upwardly adjacentsaid ring portion, and a plurality of blade members formed with notchesshaped to receive said ring portion and formed with inwardly flaringlocking lugs engageable through said last-named vertical slots abovesaid ring portion and vertically slidable in and being of sufficientwidth to be lockingly engageable in the first-named vertical slots tofasten the blade members to said lower supporting member when the uppersupporting member is threadedly engaged in the upper portion of thelower supporting member.

3. A drilling bit assembly comprising a tubular externally threadedupper supporting member adapted to be connected to a drill stem, atubular locking member rotatably secured in the lower end portion ofsaid supporting member and depending therefrom, the lower end of saidlocking member being formed with a plurality of inwardly divergentvertical slots open at their bottom ends and defining depending lockingfingers therebetween, a tubular lower supporting member having aninternally threaded upper portion threadedly engageable on the externalthreads of the upper supporting member and formed with an integral ringportion and with vertical slots outwardly adjacent said ring portion andextending above and below same and being registrable with saidfirst-named vertical slots, said lower supporting member being formedwith a downwardly tapering inner wedging surface upwardly adjacent saidring portion and the lower end of said locking member having an outsidediameter sufliciently large so that said locking fingers are wedginglyengageable with said wedging surface, and a plurality of blade membersformed with notches shaped to receive said ring portion and formed withinwardly flaring locking lugs engageable through said last-namedvertical slots above said ring portion and vertically slidable in andbeing of sufficient width to be lockingly engageable in the first-namedvertical slots to fasten the blade members to said lower supportingmember when the upper supporting member is threadedly engaged in theupper portion of the lower supporting member.

4. A drilling bit assembly comprising a tubular externally threadedupper supporting member adapted to be connected to a drill stem, atubular locking member rotatably secured in the lower end portion ofsaid supporting member and depending therefrom, the lower end of saidlocking member being formed with a plurality of inwardly divergentvertical siots open at their bottom ends and defining depending lockingfingers therebetween, a tubular lower supporting member having aninternally threaded upper portion threadedly engageable on the externalthreads of the upper supporting member and formed with an integral ringportion and with vertical slots outwardly adjacent said ring portion andextending above and below some and being registrable with saidfirst-named vertical slots, said locking fingers being vertically slitat their lower end portions to make them somewhat resilient, said lowersupporting member being formed with a downwardly tapering inner wedgingsurface upwardly adjacent said ring portion and the lower end of saidlocking member having an outside diameter sufficiently large so thatsaid locking fingers are wedgingly engageable with said wedging surface,and a plurality of blade members formed with notches shaped to receivesaid ring portion and formed with inwardly flaring locking lugsengageable through said last-named vertical slots above said ringportions and vertically slidable in and being of sutiicient width to belockingly engageable in the first-named vertical slots to fasten theblade members to said lower supporting member when the upper supportingmember is threadedly engaged in the upper portion of the lowersupporting member.

5. A drilling bit assembly comprising a tubular externally threadedupper supporting member adapted to be con nected to a drill stem, atubular locking member rotatably secured in the lower end portion ofsaid supporting member and depending therefrom, the lower end of saidlocking member being formed with a plurality of vertical slots open attheir bottom ends and defining depending locking fingers therebetween, atubular lower supporting member having an internally threaded upperportion threadedly engageable on the external threads of the uppersupporting member and formed with an integral ring portion and withvertical slots outwardly adjacent said ring portion and extending aboveand below same and being registrable with said first-named verticalslots, said vertical slots having vertical inwardly divergent sideedges, and a plurality of blade members formed with notches shaped toreceive said ring portion and formed with vertical dovetailed lockinglugs engageable through said lastnamed vertical slots above said ringportion and vertically slidable in and being of sufficient width to belockingly engageable in the first-named vertical slots to fasten theblade members to said lower supporting member when the upper supportingmember is threadedly engaged in the upper portion of the lowersupporting member.

6. A drilling bit assembly comprising a tubular externally threadedupper supporting member adapted to be connected to a drill stem, atubular locking member rotatably secured in the lower end portion ofsaid supporting member and depending therefrom, the lower end of saidlocking member being formed with a plurality of vertical slots open attheir bottom ends and defining depending locking fingers thorebetween, atubular lower supporting member having an internally threaded upperportion threadedly engageable on the external threads of the uppersupporting member and formed with an integral ring portion and withvertical slots outwardly adjacent said ring portion and extending aboveand below same and being registrable with said first-named verticalslots, said locking fingers being vertically slit at their lower endportions to make them somewhat resilient, said lower supporting memberbeing formed with a downwardly tapering inner wedging surface upwardlyadjacent said ring portion and the lower end of said locking mernberhaving an outside diameter sufiiciently large so that said lockingfingers are wedgingly engageable with said wedging surface, saidfirst-named vertical slots having vertical inwardly divergent sideedges, and a plurality of blade members formed with notches shaped toreceive said ring portion and formed immediately above said notches withvertical dovetailed locking lugs engageable through said last-namedvertical slots and vertically slidable in and being of suficeint widthto be lockingly engageable in the first-named vertical slots to fastenthe blade members to said lower supporting member when the uppersupporting member is threadedly engaged in the upper portion of thelower supporting member.

References Cited in the file of this patent UNITED STATES PATENTS1,301,121 Gordon et al Apr. 22, 1919 1,326,506 Humason Dec. 30, 19191,978,084 Howard Oct. 23, 1934 2,599,854 McMurdy et al. June 10, 19522,666,622 Hawthorne Jan. 19, 1954 2,978,049 Skidrnore et a1 Apr. 4, 1961

1. A DRILLING BIT ASSEMBLY COMPRISING A TUBULAR EXTERNALLY THREADEDUPPER SUPPORTING MEMBER ADAPTED TO BE CONNECTED TO A DRILL STEM, ATUBULAR LOCKING MEMBER ROTATABLY SECURED IN THE LOWER END PORTION OFSAID SUPPORTING MEMBER AND DEPENDING THEREFROM, THE LOWER END OF SAIDLOCKING MEMBER BEING FORMED WITH A PLURALITY OF INWARDLY DIVERGENTVERTICAL SLOTS OPEN AT THEIR BOTTOM ENDS, A TUBULAR LOWER SUPPORTINGMEMBER HAVING AN INTERNALLY THREADED UPPER PORTION THREADEDLY ENGAGEABLEON THE EXTERNAL THREADS OF THE UPPER SUPPORTING MEMBER AND FORMED WITHAN INTEGRAL RING PORTION AND WITH VERTICAL SLOTS OUTWARDLY ADJACENT SAIDRING PORTION AND EXTENDING ABOVE AND BELOW SAME AND BEING REGISTRABLEWITH SAID FIRST-NAMED VERTICAL SLOTS, AND A PLURALITY OF BLADE MEMBERSFORMED WITH NOTCHES SHAPED TO RECEIVE SAID RING PORTION AND FORMED WITHINWARDLY FLARING LOCKING LUGS ENGAGEABLE THROUGH SAID LAST-NAMEDVERTICAL SLOTS ABOVE THE RING PORTION AND VERTICALLY SLIDABLE IN ANDBEING OF SUFFICIENT WIDTH TO BE LOCKINGLY ENGAGEABLE IN THE FIRST-NAMEDVERTICAL SLOTS TO FASTEN THE BLADE MEMBERS TO SAID LOWER SUPPORTINGMEMBER WHEN THE UPPER SUPPORTING MEMBER IS THREADEDLY ENGAGED IN THEUPPER PORTION OF THE LOWER SUPPORTING MEMBER.